The price was right on a PS VR, so I got one and thought briefly about playing around with VR using Unity. The ecosystem was so locked down (and becoming an official developer such a challenge) that I gave up and never looked back.
The appeal of developing in Apple's ecosystem has always been the exposure to large audiences, the (relatively decent) tooling, and the ability to creatively actualize your ideas. That last one goes away when Apple starts looking more like Sony.
I'll leave it up to lawyers to decide if this is illegal, but I know this certainly makes me less excited about developing my next iOS/OSX app